1
|
Asmara TC, Green RJ, Suter A, Wei Y, Zhang W, Knez D, Harris G, Tseng Y, Yu T, Betto D, Garcia-Fernandez M, Agrestini S, Klein YM, Kumar N, Galdino CW, Salman Z, Prokscha T, Medarde M, Müller E, Soh Y, Brookes NB, Zhou KJ, Radovic M, Schmitt T. Emergence of Interfacial Magnetism in Strongly-Correlated Nickelate-Titanate Superlattices. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024:e2310668. [PMID: 39101291 DOI: 10.1002/adma.202310668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 06/21/2024] [Indexed: 08/06/2024]
Abstract
Strongly-correlated transition-metal oxides are widely known for their various exotic phenomena. This is exemplified by rare-earth nickelates such as LaNiO3, which possess intimate interconnections between their electronic, spin, and lattice degrees of freedom. Their properties can be further enhanced by pairing them in hybrid heterostructures, which can lead to hidden phases and emergent phenomena. An important example is the LaNiO3/LaTiO3 superlattice, where an interlayer electron transfer has been observed from LaTiO3 into LaNiO3 leading to a high-spin state. However, macroscopic emergence of magnetic order associated with this high-spin state has so far not been observed. Here, by using muon spin rotation, x-ray absorption, and resonant inelastic x-ray scattering, direct evidence of an emergent antiferromagnetic order with high magnon energy and exchange interactions at the LaNiO3/LaTiO3 interface is presented. As the magnetism is purely interfacial, a single LaNiO3/LaTiO3 interface can essentially behave as an atomically thin strongly-correlated quasi-2D antiferromagnet, potentially allowing its technological utilization in advanced spintronic devices. Furthermore, its strong quasi-2D magnetic correlations, orbitally-polarized planar ligand holes, and layered superlattice design make its electronic, magnetic, and lattice configurations resemble the precursor states of superconducting cuprates and nickelates, but with an S→1 spin state instead.
Collapse
Affiliation(s)
- Teguh Citra Asmara
- PSI Center for Photon Science, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
- European X-Ray Free-Electron Laser Facility GmbH, Holzkoppel 4, 22869, Schenefeld, Germany
| | - Robert J Green
- Department of Physics & Engineering Physics, University of Saskatchewan, 116 Science Place, Saskatoon, SK, S7N 5E2, Canada
- Stewart Blusson Quantum Matter Institute, University of British Columbia, 2355 East Mall, Vancouver, BC, V6T 1Z4, Canada
| | - Andreas Suter
- Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Yuan Wei
- PSI Center for Photon Science, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Wenliang Zhang
- PSI Center for Photon Science, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Daniel Knez
- Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, Steyrergasse 17, Graz, 8010, Austria
| | - Grant Harris
- Department of Physics & Engineering Physics, University of Saskatchewan, 116 Science Place, Saskatoon, SK, S7N 5E2, Canada
| | - Yi Tseng
- PSI Center for Photon Science, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Tianlun Yu
- PSI Center for Photon Science, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Davide Betto
- European Synchrotron Radiation Facility, 71, avenue des Martyrs, Cedex 9, Grenoble, F-38043, France
| | - Mirian Garcia-Fernandez
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Stefano Agrestini
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Yannick Maximilian Klein
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Neeraj Kumar
- Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Carlos William Galdino
- PSI Center for Photon Science, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Zaher Salman
- Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Thomas Prokscha
- Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Marisa Medarde
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Elisabeth Müller
- Electron Microscopy Facility, Paul Scherrer Institut, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Yona Soh
- Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Nicholas B Brookes
- European Synchrotron Radiation Facility, 71, avenue des Martyrs, Cedex 9, Grenoble, F-38043, France
| | - Ke-Jin Zhou
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Milan Radovic
- PSI Center for Photon Science, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| | - Thorsten Schmitt
- PSI Center for Photon Science, Paul Scherrer Institute, Forschungsstrasse 111, Villigen PSI, CH-5232, Switzerland
| |
Collapse
|
2
|
Gao Q, Fan S, Wang Q, Li J, Ren X, Biało I, Drewanowski A, Rothenbühler P, Choi J, Sutarto R, Wang Y, Xiang T, Hu J, Zhou KJ, Bisogni V, Comin R, Chang J, Pelliciari J, Zhou XJ, Zhu Z. Magnetic excitations in strained infinite-layer nickelate PrNiO 2 films. Nat Commun 2024; 15:5576. [PMID: 38956078 PMCID: PMC11220032 DOI: 10.1038/s41467-024-49940-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 06/26/2024] [Indexed: 07/04/2024] Open
Abstract
Strongly correlated materials respond sensitively to external perturbations such as strain, pressure, and doping. In the recently discovered superconducting infinite-layer nickelates, the superconducting transition temperature can be enhanced via only ~ 1% compressive strain-tuning with the root of such enhancement still being elusive. Using resonant inelastic x-ray scattering (RIXS), we investigate the magnetic excitations in infinite-layer PrNiO2 thin films grown on two different substrates, namely SrTiO3 (STO) and (LaAlO3)0.3(Sr2TaAlO6)0.7 (LSAT) enforcing different strain on the nickelates films. The magnon bandwidth of PrNiO2 shows only marginal response to strain-tuning, in sharp contrast to the enhancement of the superconducting transition temperature Tc in the doped superconducting samples. These results suggest the bandwidth of spin excitations of the parent compounds is similar under strain while Tc in the doped ones is not, and thus provide important empirics for the understanding of superconductivity in infinite-layer nickelates.
Collapse
Affiliation(s)
- Qiang Gao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Shiyu Fan
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York, NY, 11973, USA
| | - Qisi Wang
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
- Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Jiarui Li
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Xiaolin Ren
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Izabela Biało
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
- AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, 30-059, Kraków, Poland
| | - Annabella Drewanowski
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
| | - Pascal Rothenbühler
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland
| | - Jaewon Choi
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, United Kingdom
| | - Ronny Sutarto
- Canadian Light Source, Saskatoon, Saskatchewan, S7N 2V3, Canada
| | - Yao Wang
- Department of Physics and Astronomy, Clemson University, Clemson, SC, 29631, USA
| | - Tao Xiang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
- Beijing Academy of Quantum Information Sciences, Beijing, 100193, China
| | - Jiangping Hu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ke-Jin Zhou
- Diamond Light Source, Harwell Campus, Didcot, OX11 0DE, United Kingdom
| | - Valentina Bisogni
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York, NY, 11973, USA
| | - Riccardo Comin
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - J Chang
- Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland.
| | - Jonathan Pelliciari
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York, NY, 11973, USA.
| | - X J Zhou
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- Songshan Lake Materials Laboratory, Dongguan, 523808, China.
| | - Zhihai Zhu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- Songshan Lake Materials Laboratory, Dongguan, 523808, China.
| |
Collapse
|
3
|
Meineke C, Schlosser J, Zizlsperger M, Liebich M, Nilforoushan N, Mosina K, Terres S, Chernikov A, Sofer Z, Huber MA, Florian M, Kira M, Dirnberger F, Huber R. Ultrafast Exciton Dynamics in the Atomically Thin van der Waals Magnet CrSBr. NANO LETTERS 2024; 24:4101-4107. [PMID: 38507732 PMCID: PMC11010225 DOI: 10.1021/acs.nanolett.3c05010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/08/2024] [Accepted: 03/11/2024] [Indexed: 03/22/2024]
Abstract
Among atomically thin semiconductors, CrSBr stands out as both its bulk and monolayer forms host tightly bound, quasi-one-dimensional excitons in a magnetic environment. Despite its pivotal importance for solid-state research, the exciton lifetime has remained unknown. While terahertz polarization probing can directly trace all excitons, independently of interband selection rules, the corresponding large far-field foci substantially exceed the lateral sample dimensions. Here, we combine terahertz polarization spectroscopy with near-field microscopy to reveal a femtosecond decay of paramagnetic excitons in a monolayer of CrSBr, which is 30 times shorter than the bulk lifetime. We unveil low-energy fingerprints of bound and unbound electron-hole pairs in bulk CrSBr and extract the nonequilibrium dielectric function of the monolayer in a model-free manner. Our results demonstrate the first direct access to the ultrafast dielectric response of quasi-one-dimensional excitons in CrSBr, potentially advancing the development of quantum devices based on ultrathin van der Waals magnets.
Collapse
Affiliation(s)
- Christian Meineke
- Department
of Physics and Regensburg Center for Ultrafast Nanoscopy (RUN), University of Regensburg, 93040 Regensburg, Germany
| | - Jakob Schlosser
- Department
of Physics and Regensburg Center for Ultrafast Nanoscopy (RUN), University of Regensburg, 93040 Regensburg, Germany
| | - Martin Zizlsperger
- Department
of Physics and Regensburg Center for Ultrafast Nanoscopy (RUN), University of Regensburg, 93040 Regensburg, Germany
| | - Marlene Liebich
- Department
of Physics and Regensburg Center for Ultrafast Nanoscopy (RUN), University of Regensburg, 93040 Regensburg, Germany
| | - Niloufar Nilforoushan
- Department
of Physics and Regensburg Center for Ultrafast Nanoscopy (RUN), University of Regensburg, 93040 Regensburg, Germany
| | - Kseniia Mosina
- Department
of Inorganic Chemistry, University of Chemistry
and Technology Prague, 166 28 Prague 6, Czech Republic
| | - Sophia Terres
- Institute
of Applied Physics and Würzburg-Dresden Cluster of Excellence, Dresden University of Technology, 01187 Dresden, Germany
| | - Alexey Chernikov
- Institute
of Applied Physics and Würzburg-Dresden Cluster of Excellence, Dresden University of Technology, 01187 Dresden, Germany
| | - Zdenek Sofer
- Department
of Inorganic Chemistry, University of Chemistry
and Technology Prague, 166 28 Prague 6, Czech Republic
| | - Markus A. Huber
- Department
of Physics and Regensburg Center for Ultrafast Nanoscopy (RUN), University of Regensburg, 93040 Regensburg, Germany
| | - Matthias Florian
- Department
of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Mackillo Kira
- Department
of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Florian Dirnberger
- Institute
of Applied Physics and Würzburg-Dresden Cluster of Excellence, Dresden University of Technology, 01187 Dresden, Germany
| | - Rupert Huber
- Department
of Physics and Regensburg Center for Ultrafast Nanoscopy (RUN), University of Regensburg, 93040 Regensburg, Germany
| |
Collapse
|
4
|
Gozlinski T, Henn M, Wolf T, Le Tacon M, Schmalian J, Wulfhekel W. Bosonic excitation spectra of superconductingBi2Sr2CaCu2O8+δandYBa2Cu3O6+xextracted from scanning tunneling spectra. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:175601. [PMID: 38194720 DOI: 10.1088/1361-648x/ad1ca8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 01/09/2024] [Indexed: 01/11/2024]
Abstract
A detailed interpretation of scanning tunneling spectra obtained on unconventional superconductors enables one to gain information on the pairing boson. Decisive for this approach are inelastic tunneling events. Due to the lack of momentum conservation in tunneling from or to the sharp tip, those are enhanced in the geometry of a scanning tunneling microscope compared to planar tunnel junctions. This work extends the method of obtaining the bosonic excitation spectrum by deconvolution from tunneling spectra to nodald-wave superconductors. In particular, scanning tunneling spectra of slightly underdopedBi2Sr2CaCu2O8+δwith aTcof 82 K and optimally dopedYBa2Cu3O6+xwith aTcof 92 K reveal a resonance mode in their bosonic excitation spectrum atΩres≈63 meVandΩres≈61 meVrespectively. In both cases, the overall shape of the bosonic excitation spectrum is indicative of predominant spin scattering with a resonant mode atΩres<2Δand overdamped spin fluctuations for energies larger than 2Δ. To perform the deconvolution of the experimental data, we implemented an efficient iterative algorithm that significantly enhances the reliability of our analysis.
Collapse
Affiliation(s)
- Thomas Gozlinski
- Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Mirjam Henn
- Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Thomas Wolf
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Matthieu Le Tacon
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Jörg Schmalian
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
- Institute for Theory of Condensed Matter, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Wulf Wulfhekel
- Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
- Institute for Quantum Materials and Technologies, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| |
Collapse
|
5
|
Scott K, Kisiel E, Boyle TJ, Basak R, Jargot G, Das S, Agrestini S, Garcia-Fernandez M, Choi J, Pelliciari J, Li J, Chuang YD, Zhong R, Schneeloch JA, Gu G, Légaré F, Kemper AF, Zhou KJ, Bisogni V, Blanco-Canosa S, Frano A, Boschini F, da Silva Neto EH. Low-energy quasi-circular electron correlations with charge order wavelength in Bi 2Sr 2CaCu 2O 8+δ. SCIENCE ADVANCES 2023; 9:eadg3710. [PMID: 37467326 DOI: 10.1126/sciadv.adg3710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Accepted: 06/16/2023] [Indexed: 07/21/2023]
Abstract
Most resonant inelastic x-ray scattering (RIXS) studies of dynamic charge order correlations in the cuprates have focused on the high-symmetry directions of the copper oxide plane. However, scattering along other in-plane directions should not be ignored as it may help understand, for example, the origin of charge order correlations or the isotropic scattering resulting in strange metal behavior. Our RIXS experiments reveal dynamic charge correlations over the qx-qy scattering plane in underdoped Bi2Sr2CaCu2O8+δ. Tracking the softening of the RIXS-measured bond-stretching phonon, we show that these dynamic correlations exist at energies below approximately 70 meV and are centered around a quasi-circular manifold in the qx-qy scattering plane with radius equal to the magnitude of the charge order wave vector, qCO. This phonon-tracking procedure also allows us to rule out fluctuations of short-range directional charge order (i.e., centered around [qx = ±qCO, qy = 0] and [qx = 0, qy = ±qCO]) as the origin of the observed correlations.
Collapse
Affiliation(s)
- Kirsty Scott
- Department of Physics, Yale University, New Haven, CT 06520, USA
- Energy Sciences Institute, Yale University, West Haven, CT 06516, USA
| | - Elliot Kisiel
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Timothy J Boyle
- Department of Physics, Yale University, New Haven, CT 06520, USA
- Energy Sciences Institute, Yale University, West Haven, CT 06516, USA
- Department of Physics and Astronomy, University of California, Davis, CA 95616, USA
| | - Rourav Basak
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Gaëtan Jargot
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Québec J3X 1S2, Canada
| | - Sarmistha Das
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | | | | | - Jaewon Choi
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, UK
| | - Jonathan Pelliciari
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Jiemin Li
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Yi-De Chuang
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ruidan Zhong
- Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - John A Schneeloch
- Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Genda Gu
- Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - François Légaré
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Québec J3X 1S2, Canada
| | - Alexander F Kemper
- Department of Physics, North Carolina State University, Raleigh, NC 27695, USA
| | - Ke-Jin Zhou
- Diamond Light Source, Harwell Campus, Didcot OX11 0DE, UK
| | - Valentina Bisogni
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Santiago Blanco-Canosa
- Donostia International Physics Center (DIPC), 20018 Donostia-San Sebastian, Basque Country, Spain
- IKERBASQUE, Basque Foundation for Science, 48013 Bilbao, Spain
| | - Alex Frano
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
- Canadian Institute for Advanced Research, Toronto, ON M5G 1M1, Canada
| | - Fabio Boschini
- Centre Énergie Matériaux Télécommunications, Institut National de la Recherche Scientifique, Varennes, Québec J3X 1S2, Canada
- Quantum Matter Institute, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Eduardo H da Silva Neto
- Department of Physics, Yale University, New Haven, CT 06520, USA
- Energy Sciences Institute, Yale University, West Haven, CT 06516, USA
- Department of Physics and Astronomy, University of California, Davis, CA 95616, USA
- Department of Applied Physics, Yale University, New Haven, CT 06520, USA
| |
Collapse
|
6
|
Wang Z, Zou C, Lin C, Luo X, Yan H, Yin C, Xu Y, Zhou X, Wang Y, Zhu J. Correlating the charge-transfer gap to the maximum transition temperature in Bi 2Sr 2Ca n-1Cu nO 2n+4+δ. Science 2023; 381:227-231. [PMID: 37440647 DOI: 10.1126/science.add3672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 06/06/2023] [Indexed: 07/15/2023]
Abstract
As the number of CuO2 layers, n, in each unit cell of a cuprate family increases, the maximum transition temperature (Tc,max) exhibits a universal bell-shaped curve with a peak at n = 3. The microscopic mechanism of this trend remains elusive. In this study, we used advanced electron microscopy to image the atomic structure of cuprates in the Bi2Sr2Can-1CunO2n+4+δ family with 1 ≤ n ≤ 9; the evolution of the charge-transfer gap size (Δ) with n can be measured simultaneously. We determined that the n dependence of Δ follows an inverted bell-shaped curve with the minimum Δ value at n = 3. The correlation between Δ, n, and Tc,max may clarify the origin of superconductivity in cuprates.
Collapse
Affiliation(s)
- Zechao Wang
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Key Laboratory of Advanced Materials (MOE), The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing, P.R. China
- Ji Hua Laboratory, Foshan, Guangdong, P.R. China
| | - Changwei Zou
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, P.R. China
| | - Chengtian Lin
- Max Planck Institute for Solid State Research, Stuttgart, Germany
| | - Xiangyu Luo
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, P.R. China
| | - Hongtao Yan
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, P.R. China
| | - Chaohui Yin
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, P.R. China
| | - Yong Xu
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, P.R. China
- New Cornerstone Science Laboratory, Frontier Science Center for Quantum Information, Beijing, P.R. China
- RIKEN Center for Emergent Matter Science (CEMS), Wako, Japan
| | - Xingjiang Zhou
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, P.R. China
| | - Yayu Wang
- State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing, P.R. China
- New Cornerstone Science Laboratory, Frontier Science Center for Quantum Information, Beijing, P.R. China
| | - Jing Zhu
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Key Laboratory of Advanced Materials (MOE), The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing, P.R. China
- Ji Hua Laboratory, Foshan, Guangdong, P.R. China
| |
Collapse
|
7
|
Kuz'min VI, Nikolaev SV, Korshunov MM, Ovchinnikov SG. One- and Two-Particle Correlation Functions in the Cluster Perturbation Theory for Cuprates. MATERIALS (BASEL, SWITZERLAND) 2023; 16:4640. [PMID: 37444953 DOI: 10.3390/ma16134640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/16/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023]
Abstract
The physics of high-Tc superconducting cuprates is obscured by the effect of strong electronic correlations. One way to overcome this problem is to seek an exact solution at least within a small cluster and expand it to the whole crystal. Such an approach is at the heart of cluster perturbation theory (CPT). Here, we developed CPT for the dynamic spin and charge susceptibilities (spin-CPT and charge-CPT), with the correlation effects explicitly taken into account by the exact diagonalization. We applied spin-CPT and charge-CPT to the effective two-band Hubbard model for the cuprates obtained from the three-band Emery model and calculated one- and two-particle correlation functions, namely, a spectral function and spin and charge susceptibilities. The doping dependence of the spin susceptibility was studied within spin-CPT and CPT-RPA, that is, the CPT generalization of the random phase approximation (RPA). In the underdoped region, both our methods resulted in the signatures of the upper branch of the spin excitation dispersion with the lowest excitation energy at the (π,π) wave vector and no presence of low-energy incommensurate excitations. In the high doping region, both methods produced a low energy response at four incommensurate wave vectors in qualitative agreement with the results of the inelastic neutron scattering experiments on overdoped cuprates.
Collapse
Affiliation(s)
- Valerii I Kuz'min
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Akademgorodok, 660036 Krasnoyarsk, Russia
| | - Sergey V Nikolaev
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Akademgorodok, 660036 Krasnoyarsk, Russia
- Siberian Federal University, Svobodny Prospect 79, 660041 Krasnoyarsk, Russia
| | - Maxim M Korshunov
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Akademgorodok, 660036 Krasnoyarsk, Russia
- Siberian Federal University, Svobodny Prospect 79, 660041 Krasnoyarsk, Russia
| | - Sergey G Ovchinnikov
- Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Akademgorodok, 660036 Krasnoyarsk, Russia
- Siberian Federal University, Svobodny Prospect 79, 660041 Krasnoyarsk, Russia
| |
Collapse
|
8
|
Wang Z, Pei K, Yang L, Yang C, Chen G, Zhao X, Wang C, Liu Z, Li Y, Che R, Zhu J. Topological spin texture in the pseudogap phase of a high-T c superconductor. Nature 2023; 615:405-410. [PMID: 36813970 DOI: 10.1038/s41586-023-05731-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 01/13/2023] [Indexed: 02/24/2023]
Abstract
An outstanding challenge in condensed-matter-physics research over the past three decades has been to understand the pseudogap (PG) phenomenon of the high-transition-temperature (high-Tc) copper oxides. A variety of experiments have indicated a symmetry-broken state below the characteristic temperature T* (refs. 1-8). Among them, although the optical study5 indicated the mesoscopic domains to be small, all these experiments lack nanometre-scale spatial resolution, and the microscopic order parameter has so far remained elusive. Here we report, to our knowledge, the first direct observation of topological spin texture in an underdoped cuprate, YBa2Cu3O6.5, in the PG state, using Lorentz transmission electron microscopy (LTEM). The spin texture features vortex-like magnetization density in the CuO2 sheets, with a relatively large length scale of about 100 nm. We identify the phase-diagram region in which the topological spin texture exists and demonstrate the ortho-II oxygen order and suitable sample thickness to be crucial for its observation by our technique. We also discuss an intriguing interplay observed among the topological spin texture, PG state, charge order and superconductivity.
Collapse
Affiliation(s)
- Zechao Wang
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Key Laboratory of Advanced Materials (MOE), The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing, People's Republic of China
- Ji Hua Laboratory, Foshan, People's Republic of China
| | - Ke Pei
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Liting Yang
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Chendi Yang
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Guanyu Chen
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Xuebing Zhao
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
- Zhejiang Laboratory, Hangzhou, People's Republic of China
| | - Chao Wang
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
- Zhejiang Laboratory, Hangzhou, People's Republic of China
| | - Zhengwang Liu
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China
| | - Yuan Li
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, People's Republic of China.
- Collaborative Innovation Center of Quantum Matter, Beijing, People's Republic of China.
| | - Renchao Che
- Laboratory of Advanced Materials, Department of Materials Science and Shanghai Key Lab of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, People's Republic of China.
| | - Jing Zhu
- National Center for Electron Microscopy in Beijing, School of Materials Science and Engineering, Key Laboratory of Advanced Materials (MOE), The State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing, People's Republic of China.
- Ji Hua Laboratory, Foshan, People's Republic of China.
| |
Collapse
|
9
|
Domański M, van Leusen J, Metzelaars M, Kögerler P, Grochala W. Ag(II) as Spin Super-Polarizer in Molecular Spin Clusters. J Phys Chem A 2022; 126:9618-9626. [PMID: 36521028 PMCID: PMC9806831 DOI: 10.1021/acs.jpca.2c06032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Using quantum mechanical calculations, we examine magnetic (super)exchange interactions in hypothetical, chemically reasonable molecular coordination clusters containing fluoride-bridged late transition metals or selected lanthanides, as well as Ag(II). By referencing to analogous species comprising closed-shell Cd(II), we provide theoretical evidence that the presence of Ag(II) may modify the magnetic properties of such systems (including metal-metal superexchange) to a surprising degree, specifically both coupling sign and strength may markedly change. Remarkably, this happens in spite of the fact that the fluoride ligand is the least susceptible to spin polarization among all monoatomic ligands known in chemistry. In an extreme case of an oxo-bridged Ni(II)2 complex, the presence of Ag(II) leads to a nearly 17-fold increase of magnetic superexchange and switching from antiferro (AFM)- to ferromagnetic (FM) coupling. Ag(II)─with one hole in its d shell that may be shared with or transferred to ligands─effectively acts as spin super-polarizer, and this feature could be exploited in spintronics and diverse molecular devices.
Collapse
Affiliation(s)
- Mateusz Domański
- Center
of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02089Warsaw, Poland
| | - Jan van Leusen
- Institut
für Anorganische Chemie, RWTH Aachen
University, 52056Aachen, Germany
| | - Marvin Metzelaars
- Institut
für Anorganische Chemie, RWTH Aachen
University, 52056Aachen, Germany
| | - Paul Kögerler
- Institut
für Anorganische Chemie, RWTH Aachen
University, 52056Aachen, Germany,
| | - Wojciech Grochala
- Center
of New Technologies, University of Warsaw, Zwirki i Wigury 93, 02089Warsaw, Poland,
| |
Collapse
|
10
|
Mechanism of superconductivity in the Hubbard model at intermediate interaction strength. Proc Natl Acad Sci U S A 2022; 119:e2205048119. [PMID: 35947620 PMCID: PMC9388079 DOI: 10.1073/pnas.2205048119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We study the fluctuations responsible for pairing in the d-wave superconducting state of the two-dimensional Hubbard model at intermediate coupling within a cluster dynamical mean-field theory with a numerically exact quantum impurity solver. By analyzing how momentum- and frequency-dependent fluctuations generate the d-wave superconducting state in different representations, we identify antiferromagnetic fluctuations as the pairing glue of superconductivity in both the underdoped and the overdoped regime. Nevertheless, in the intermediate coupling regime, the predominant magnetic fluctuations may differ significantly from those described by conventional spin fluctuation theory.
Collapse
|